Apple has released the following change-log alongside the iOS 7.0 Beta 6 release, and its probably worth the read if you are planning to download the update.
This update addresses an issue with iTunes in the Cloud, where some purchases may download or play unexpected items. If you have any devices running previous versions of iOS 7 beta, you must:
- Install iOS 7 beta 6
- Install the ResetMusicAndVideosLibraries configuration profile
- From Settings > Music, tap the Reset Media Library button
- Restart the device
So if you are a registered developer head over to developer.apple.com/programs/ios/ and sign in with your Apple ID. If you haven't registered for the developer program and wish to try out the latest version of iOS, you can register for an account ($99/year in the United States, or £60/year in the UK) and learn how to download and install the update on your iPhone, iPad or iPod Touch.